• The Plant Pathology Journal
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• v.15 no.3
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• pp.152-157
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• 1999

An antibiotic compound was isolated from the culture of an antagonist against Fusarium oxysporum f. sp. sesami, Bacillus polymyxa strain KB-8, and tested for the control of Fusarium wilt of sesame in greenhouse conditions. Optimum conditions for culturing the antagonist to obtain the maximum antibiotic activity were determined using different culture media, initial medium acidity, and incubation periods for which yeast -malt extract agar with the initial acidity of pH 5 and over 13 days culture were best. Antibiotic substances extracted by methanol had 2 main fractions, KB-8A and KB-8B, in thin layer chromatography (OLC) with Rf values of 0.35 and 0.67 in a solvent system of chloroform : methanol = 7 : 3. The fraction KB-8A wa purified further by XAD-2, silica gel and Sephadex LH-20 column chromatography, and crystalization. Its minimum inhibitory concentrations (MICs) were $12.8\mu\textrm{g}$/ml for F. oxysporum and Alternaria mali, $6.4\mu\textrm{g}$/ml for Colletotrichum gloeosporioides and Rhizoctonia solani, and $3.2\mu\textrm{g}$/ml for Phytophthora capsici. Soil drenching of antibiotic KB-8A in the concentrations of $13.0\mu\textrm{g}$/ml and $26.0\mu\textrm{g}$/ml effectively inhibited the Fusarium wilt of sesame in a greenhouse test, which appeared to be comparable to the fungicide benlate of $6.5\mu\textrm{g}$ a. i./ml.

• The Korean Journal of Mycology
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• v.41 no.2
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• pp.74-80
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• 2013

Fourteen new records of yeasts were screened from one hundred thirty-three yeasts strains which were isolated from wild flowers in east, west and south coast near areas and inland areas, Korea. Candida silvae, Cryptococcus terrestris and Auriculibuller fuscus were newly isolated from wild flowers collected at Donghae and Andong, respectively. Candida quercitrusa, Hanseniaspora opuntiae, Sporobolomyces carnicolor, Candida saopaulonensis and Sporobolomyces phaffii were newly isolated from wild flowers in Geumsan-gun and Taean-gun in Chungcheongnam-do, respectively. Candida oleophila and Jaminaea angkoriensis were newly identified from flowers in Yesan-gun and Hannaella zeae was also newly identified from flowers of Daecheon. Hanseniaspora vineae and two other yeast strains including Pseudozyma hubeiensis were newly isolated and identified from flowers collected at Gwangju and Wando-gun, respectively. Morphological and physiological characteristics of their new recorded yeasts were investigated.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.752-757
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• 2005

Changes in milk quality during storage of extended shelf life milk (ESL milk) and non-ESL milk were evaluated. No significant differences were observed between ESL and typical ultra high temperature-treated (UHT) milk in physicochemical properties including non-casein nitrogen (NCN) content, whey protein nitrogen index (WPNI), and L-ascorbic acid content. Low temperature and long time-treated milk (LTLT milk) had significantly higher NCN content and WPNI than those of UHT milk. In terms of microbial quality, yeast, molds, coliforms, and other bacteria were not detected in ESL milk during entire storage (21 days after expiration date) period at 4 and $25^{\circ}C$, while LTLT milk was more susceptible to microbial infection. Rats fed ESL milk resulted in significantly higher body weight, average daily gain, and feed efficiency than those given UHT milk. These results suggest ESL milk maintains better microbial quality than typical UHT milk, particularly during storage under extended refrigeration and at high temperature.

• Microbiology and Biotechnology Letters
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• v.33 no.2
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• pp.90-95
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• 2005

An Actinomycetes producing an anti-VRSA (vancomycin-resistant Staphylococcus aureus) substance was isolated from soil. The cultural, morphological, physiological and phylogenetic analyses of an isolated strain were investigated for identification. Cultural characteristics based on ISP (International Streptomyces Project) were as follows: white aerial mycelium, yellow reverse side, and good growth on various medium. Also, the isolate did not produce the soluble pigment. Morphological characteristics were showed cylindrical spore chain and smooth spore surface by SEM (Scanning Electron Microscope). Physiological characteristics were showed LL-type by DAP isomer analysis and detected glycine, glutamic acid and alanine. A phylogenetic analysis of the 16S rDNA provided a clue that the isolated strain was actually a member of the genus Streptomyces, because the determined sequence exhibited a higher homology with Streptomyces echinatus. The isolate was identified to be a genus of Streptomyces sp.. The optimal culture conditions for the maximum production of anti-VRSA substance by Streptomyces sp. were attained in a culture medium composed of $2.0\%$ (w/v) glucose, and $0.4\%$ (w/v) yeast extract. The anti-VRSA substance was highly produced after 5 days of culture. Optimal pH and temperature conditions for the production of anti-VRSA substance were pH 7.0 and $28^{\circ}C$, respectively.

• The Korean Journal of Mycology
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• v.40 no.3
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• pp.141-144
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• 2012

Total 50 species, 80 strains: Eighty strains of yeasts were isolated from wild flowers of Daejeon city and its surroundings in Korea. Isolated yeasts were identified by comparison of their PCR-amplified 18s rDNA V3 region or internal transcribed spacer-2 (ITS-2) genes with BLAST database. Among them, 32 species, 54 strains of yeasts were isolated and identified from wild flowers of Daejeon city, and Cryptococcus species were dominant yeasts. Furthermore, 18 species, 26 strains of yeasts were isolated and identified from wild flowers of Geumsan-gun and Nonsan-gun, Chungcheongnam-do in Korea, and also Candida species and Pseudozyma species were dominant yeasts.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.187-187
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• 2003

To examine the effect of packaging method on strawberry, tomato, and plum quality, the rate of weight loss, Hunter a value, decay rate, anthocyanin contents, and microbial (total bacterial counts, mold and yeast, and pseudomonas) changes were determined during storage. Strawberry was packaged with low density polyethylene (LDPE). Tomato and plum were packaged with high density polyethylene film (HDPE). Strawberries, tomatoes, and plums were then stored at 4$^{\circ}C$ and 20$^{\circ}C$, respectively. LDPE package was the most effective on the decrease of decay rate of strawberry and the rate of weight loss for packaged strawberry was lower than that of the non-packaged. HDPE package was the most effective on the rate of weight loss during storage of tomatoes and plums regardless of storage temperature. Hunter a value increased during storage. Anthocyanin contents of plums increased overall with increasing storage time, and plums stored without package were changed more than those with package. Microbial changes of strawberry, tomato, and plum stored at 4$^{\circ}C$ and 20$^{\circ}C$ were monitored during storage. Packaging method did not affect the microbial change, yet temperature did affect the microbial change significantly. These results indicate that storage of these commodities at 4$^{\circ}C$ should be recommended in terms ,of microbial safety as well as quality and shelf-life.

• Journal of fish pathology
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• v.17 no.1
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• pp.57-66
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• 2004

Effects of oral administration with fermented product from sewage in land-based seawater fish farm on haematological disturbance in the olive flounder, Paralichthys olivaceus was investigated. After 4 weeks of conditioning with a basal diet, fish were divided into 4 groups and provided experimental diet (0.1, 0.5, 1.0 and 2.0%) supplement of fermented sewage for 80 days. Proximal analysis was performed for the product of sewage which was fermented by lactic acid and yeast. RBC count, hemoglobin concentration and hematocrit value were increased according to the treated periods, however, no statistical difference was observed between control and treatment groups. There were no significant difference in serum organic, inorganic compounds and enzyme activities between control and treatment groups. This study hypothesized that the supplement of fermented product from sewage in land-based seawater fish farm might be an additive supplement for source of fish diet in view of haematological examination. Recycling of the sewage may be an economic artificial sources of diet for fish aquaculture practices.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.4
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• pp.602-609
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• 2015

In this study, for modernization of Korean traditional fermented milk, Tarak was made using four kinds of commercial Makgeolli based on the ancient cookbook Suwoonjabbang. Samples of Tarak were periodically collected during 24 h of fermentation at $37^{\circ}C$. After fermentation, changes in pH, titration acidity, and viscosity were analyzed. Fermentation metabolites, including organic acids and free sugars, were analyzed by HPLC. Numbers of yeast and lactic acid bacteria during 24 h of fermentation were measured. The pH of Tarak significantly decreased (P<0.01), whereas its acidity significantly increased (P<0.01) during fermentation. The viscosity increased during 8~24 h of fermentation until curd was separated in Tarak. The level of ethanol increased from 0.37~0.52 mg/mL to 0.51~0.71 mg/mL during 24 h of fermentation. Lactic acid and lactose were the major organic acid and free sugar in Tarak, respectively. The number of lactic acid bacteria increased from 5.23~6.25 log CFU/mL to 9.87~10.41 log CFU/mL at the beginning during 24 h of fermentation. The number of yeast increased from 5.14~6.47 log CFU/mL to 6.99~7.73 at the beginning during 24 h of fermentation at $37^{\circ}C$. The major strains of Tarak were Pediococcus acidilactici, Lactobacillus fermentun, Lactobacillus curvatus, and Saccharomyces cerevisiae. Therefore, we concluded that Tarak was a fermented milk by both lactic acid bacteria and yeast, which was similar to koumiss or kefir.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.4
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• pp.437-442
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• 2012

Red yeast rice (RER) has been used in China for centuries for its medicinal properties and is an increasingly popular alternative lipid-lowering treatment. This study was carried out to estimate the antioxidant properties of RER extracts. The ethyl acetate extract exhibited the DPPH radical scavenging activity of 85% at 0.2 mg/mL and $IC_{50}$ 0.13 mg/mL. A significant proportion of hydroxyl radicals in a cuvette were scavenged: 44.2% at 2.5 ${\mu}g$/mL, 74.1% at 5.0 ${\mu}g$/mL, and >100% at 10 ${\mu}g$/mL. The $HepG_2$ cells pre-treated with RER ethyl acetate extract reduced the hydroxyl radicals significantly compared to the control cells. Oxidative DNA damage was measured using a Comet assay. The RER ethyl acetate extract did not induce any DNA damage per se, and appeared to enhance the resistance to DNA damage caused by an oxidant challenge with $H_2O_2$, whereas lovastatin increased the level of DNA damage in the cells in both the unstressed (no oxidant) and those stressed with $H_2O_2$. The relative gene expression of the antioxidant enzymes in $HepG_2$ cells were also affected by the RER ethyl acetate extract. The $HepG_2$ cells were pre-incubated with the RER ethyl acetate extract, and then stressed with $H_2O_2$ or left unstressed (no oxidant). In the unstressed cells, superoxide dismutase (Cu/Zn SOD) and glutathione peroxidase (GPx) were increased significantly 3.25-fold and 2.67-fold, respectively, whereas in the stressed cells, the catalase (CAT) level was increased by 4.64-fold and 7.0-fold at 5 ${\mu}g$/mL and 10 ${\mu}g$/mL, respectively, compared to those of the control. From these results, RER appears to be effective in suppressing oxidative stress.

• Korean Journal of Poultry Science
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• v.34 no.3
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• pp.157-163
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• 2007

To examine the effects of dietary organic selenium and vitamin E supplementation on egg production, egg weight, daily egg mass, feed intake, feed conversion, egg quality, lipid-soluble antioxidative capacity (ACL) in egg yolk, and selenium retention of egg in laying hens, Hy-Line laying hens of 77 wk old were replaced in the individual cage for 12 week. A corn-soybean meal based diet was supplemented with 0 (control), vitamin E 100 IU/kg and the combination of 0.9 ppm Se from selenium yeast (SY) and vitamin E 50, 100 and 150 IU/kg. Egg production and daily egg mass were significantly increased (P<0.05) in supplemental vitamin E 100 IU, and 0.9 ppm SY + vitamin E 50 IU than control for the whole experimental period. However, feed intake and feed conversion were not affected by supplemental vitamin E and SY. Haugh unit was significantly (P<0.05) higher in supplemental vitamin E 100 IU and 0.9 ppm SY + vitamin E 50 IU than control, 0.9 ppm SY + vitamin E 100 and 0.9 ppm SY + 150 IU in week 5. Haugh unit of the eggs during storage decreased significantly(P<0.05) from day 1 to day 11. However, Haugh units of the eggs from 0.9 ppm SY + vitamin E 150 IU treated groups did not decreased significantly until day 5. Yolk color was significantly (P<0.05) higher in 0.9 ppm SY + vitamin E 50 and 0.9 ppm SY + 100 IU than other treatment groups in week 1. Selenium concentrations of egg were significantly increased (P<0.05) in 0.9 ppm SY + vitamin E than control and vitamin E 100 IU groups. Lipid-soluble antioxidative capacity (ACL) in egg yolk was significantly (P<0.05) higher in supplemental combination of 0.9 ppm SY + vitamin E 150 IU when compared to those of other treatment groups.